The ultimate objective of this research is to determine the etiology and pathogenesis of atherosclerosis and its cardiovascular sequelae. This objective is approached by combining morphologic, experimental, epidemiologic, chemical and biometric methods. The possible etiologic relationships of certain environmental factors and disease states to arterial lesions, coronary heart disease and sudden death are being studied using a community pathology approach. This study of a 100 percent sample of deceased men, 25-44 years of age, from the biracial community of New Orleans includes a detailed examination of the heart, coronary arteries, and the postmortem characteristics of the 80 percent which are autopsied. An explanation for an apparent anomalous difference in coronary heart disease in young Negro and Caucasian men is being sought. Experimental studies in nonhuman primates are being used to (1) examine the effect of suspected etiologic agents on diet-induced arterial lesions, (2) to determine the effect of dietary changes on reversal of lesions and on cholesterol metabolism, and (3) to examine the role of cellular components in the pathogenesis of atherosclerotic lesions.